Measures of health literacy and measures of cognitive function both predict health knowledge, health behaviors, and health outcomes. A clear theoretical and empirical relationship exists between these two variables, and recently investigators have questioned whether the most commonly used tests of reading ability in health care may actually be measuring cognitive function. However, no study has fully explored this relationship. The overall objective of this study is to investigate the relationship between health literacy and domains of cognitive function in older adults, and to determine how these factors predict one's ability to perform routine health activities. Specific aims of our study are to: 1) Explore associations between the most common measures of health literacy (REALM, TOFHLA, NVS) with tests of cognitive function in older adults, 2a) Investigate the association between tests of cognitive function and performance on various health learning tasks in older adults, and 2b) Determine the relationship between the REALM, TOFHLA, and NVS with older adults'performance on health learning tasks after controlling for tests of cognitive function. Several hypotheses have also been identified. We will conduct in-depth, structured interviews among a diverse cohort of 1,000 community-dwelling older adults ages 55 to 74 recruited from multiple sites. Detailed assessments of cognitive function, health literacy skills, and the ability to perform routine health learning tasks will be administered to all subjects over a two- session interview process to reduce respondent burden. For some of the health learning tasks, alternative formats (i.e. multimedia, enhanced print) and instructional methods (i.e. teach-to-goal) are available. We will randomly assign subjects to receive either the standard or alternative format of the task. The efficacy of these potential strategies to improve performance on the specified health learning tasks, and the interactions with cognitive measures will be investigated Research activities will be carried out over a 36 month period in three phases: 1) preparation, 2) implementation, and 3) analysis. Structural Equation Modeling analyses will be used to elucidate the various relationships between health literacy measures, tests of cognition, and performance on health learning tasks. Exploratory analyses will also evaluate the efficacy of design strategies to improve health information materials.